Main > Monitor/Video Forum
Wells Gardner D9200 - Horizontal Collapse?
Rocketeer2001:
After doing the thermal tests, I then decided to do some voltage checks. Hard to do with the monitor still in the cabinet, so I removed the chassis, located components of interest, hooked up jumper leads to them, labeled the leads, then put it all back in the cabinet and flicked it on. I could then test each lead with a multimeter from outside the cabinet without sticking my hands in dangerous places.
Something odd I noticed is when doing the thermal camera checks, I had the game board off and only the monitor turned on, and the clicking sound would be constant. I also had no static feeling on the monitor glass.
When I was testing the voltages later on, it clicked a few times when I turned it on, and didn't click again. Now it has a slight buzz coming from the neck board and the monitor has static if I run my hand over the glass, so the flyback must be working now, right?
It no longer clicks when I turn it on. It just behaves like it's not getting a signal and still doesn't display the 'no signal' message.
Except for one round of tests where I actually got some color and very distorted blips of the 'no signal' image, but I could never make it appear again. ???
I can hear the tube static trickle away when I shut the monitor off, so it sounds like it is degaussing.
Have a look at my marked-up screenshot of the schematic. I've noted where I tested for voltages and the results I got. It seems to me like maybe the IC404 is my issue if you look at the voltages on their pins, and take into account the thermal image of this chip. It's very strange that I get 0V near R490, but have 11.9v at R493. I did test those resistors on-board and their values are correct, but maybe I'll pull them and see if they're still good.
Or maybe it's T401 not creating the voltage IC404 needs to operate?
Or maybe T403 isn't working and it's messing up T401?
At C432 beside T401, I get ZERO voltage. I think it's supposed to be around 18v?
I also tested the Neck Board voltages at the connectors, and compared to what the printed values said, I got:
4.98v (should be 5v)
7.19v (should be 8v)
170.2V (should be 170v)
11.93v (should be 12v)
Lastly, I tested these parts and they're good:
Q404
Q419
C432
D416
D423
R438
R440
R492
R491
I'm thinking of just getting an IC404 and slapping it in there and seeing what happens. Unless you guys have some other tests I should do to narrow this down, or suggest some other parts I should get at the same time just in case I get another domino effect.
Rocketeer2001:
I'm back with my final report.
I determined that IC404 wasn't putting out the correct voltages so I opted to try replacing it. Before doing so I checked everything around it one last time and found the fusing resistor R415 to be way out of spec. Supposed to be 22 ohms and it had around 230ohms. I went to get a replacement but couldn't fit it in 1/4w, so had to get it in 1/3w instead.
After replacing those two parts, I put the board back in the machine and flicked on the power. Black screen, no high voltage sizzle in the screen, and the HOT was back to repetitive clicking.
Anticipating that this might not solve the problem, while ordering those parts I also ordered a bunch of other parts that could be the problem, along with spares of commonly reported failed components. Since my first attempt didn't work, I figured I may as well toss all these parts in, and then I'd know for sure that A) one of those parts was the issue, or B) none of those parts were the issue but at least I'd know they were all new.
I tested each old part as I removed it, just to see if there was anything amiss. Here's what I replaced:
IC401
IC402
IC803 - Test result said "unknown part". I assume that means it was dead.
IC805
IC806 - Test result said "unknown part". I assume that means it was dead.
C810 - This part was already new, but the troubleshooting guide said to replace it with a 270uf 35v cap instead of the 220uf if you have issues, so I did.
Q402 and Q401 - test result was a little off compared to Q402
Q426 and Q427
Q413 and Q407 - test result was a little off compared to Q413
Q105, Q403, Q405, Q412, Q419, Q423, Q428
After changing all of those, I turned it on aaaaaaand....we're back to the same condition. No improvement.
And with that, I give up. :dunno
I've been banging my head against this wall for long enough :banghead:.
This D9200 is a real piece of work! I've been trying to fix this thing for months and it sounds like these have a history of being great when they work and being a nightmare when they don't. I've only experienced the latter so in my limited experience I'm calling this thing a piece of junk!
I've found an alternate solution. I came across a free 27" Toshiba 27AFX55 TV on kijiji. I went and picked it up and it works great. Absolutely nothing wrong with it. This series of TV's is well documented on how to do an RGB input mod, so that's what I'm going to do and then shove it into the cabinet. I do get a slight downgrade in resolution quality because the Big Buck Hunter game board outputted medium resolution, but this tv will only do standard resolution. I never really got to see the D9200 run for more than 5 minutes, so I'll never know what I was missing anyways. I can set the game board to run in standard resolution.
Here's some photos of the new TV running some tests. First one was me learning that I can't run the game in medium resolution (31.5khz) on a consumer TV that can only do 15khz. Second photo is of my PS1 hooked up with an RGB scart cable to the component input. Looks pretty sharp to me. Photos don't do it justice.
Thanks to everyone that attempted to help! :notworthy:
It was a long road to get here, but unfortunately we'll have to toss this thread into the every-growing category of D9200 repair failures.
lilshawn:
--- Quote from: Rocketeer2001 on May 30, 2024, 11:58:35 pm ---these have a history of being great when they work and being a nightmare when they don't.
--- End quote ---
this is the most accurate statement about the Wells Gardner D9xxx series chassis that has ever been written.
I would like to say they are over-engineered... but it's not really. it's... under-engineered overly complicated engineering. it makes for a very temperamental setup that if you can get it immediately when it fails (ideally before) you are fine. the problem lies in the sections that keep running after a section has failed and it causes more failures in related and adjacent circuits. if they had checks in place to detect failures and shut things down, we wouldn't be in the situations we do with them.
Rocketeer2001:
Wellp, my plot to RGB mod a TV were thwarted. See this post for the horribly long story:
https://forum.arcadecontrols.com/index.php/topic,168676.msg1772715.html#msg1772715
Or a quick summary:
I can't use a TV because I can't output 15khz standard resolution from the Big Buck Hunter game board.
If you bought this game as a kit to retrofit an existing cabinet, you got the board that can switch resolutions. If you bought the whole machine from Incredible Technologies (oh the irony of the name), you got a board that's locked to medium EGA resolution. This makes no sense to me; it has the darn dip-switches on the board, but the jerks software locked it to medium resolution. WHY?!!?
I can't do a TV mod it'll never display the medium res image this stupid game spits out. Looks like I'll have to fix this D9200 since it's the only EGA monitor I got.
My options are:
1. Keep throwing parts at it with every free moment I have
2. Find someone to fix it
3. Get a universal chassis board from ebay (not sure if they have any that do EGA though...)
It's current state is:
When turned on it will rapid fire a bunch of clickity noises for about 30 seconds, then goes silent. No static charge on the screen, and everything is black. If I leave it on too long it'll start burning out components, as I did when I was trying to measure voltages.
Rocketeer2001:
I called another well known local repair shop today. They told me they were months behind with a backlog of work, and even if they weren't, they don't want to touch the D9200 with a 10ft joystick. Said the digital monitors are a pain to repair.
So either I'm back to fixing it myself, or...I may have found a lead on a WG K7500 chassis. Those output med res for a 27" monitor, so it should work on this tube, right? I'll check my yoke impedence to make sure it matches, but is the k7500 chassis a good one? More reliable than the D9200?